carb help

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mopardrt

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K guys I have a rebuilt 360 bored 30. over heads decked changing cams so not sure about duration keith black pistons 10 to 1 comp and a victor 340 intake Need to buy a new carb what Holley should I go with I want to stick to holley I have a suposed rebult 750 single pumper on right now and it just dosent run right
 
.............R u sure its the carb, if so maybe it needs jetted up or down...could be a vacuum leak or timing issue......kim.......
 
pm me with ur number and ill walk u thru setting it up
 
I just put a holley 770 street avenger on mine and im real happy with it. Mine turned out to be vacume leak but Isure like the new carb.
 
.............R u sure its the carb, if so maybe it needs jetted up or down...could be a vacuum leak or timing issue......kim.......


ya we have played with it and played with it the jets dont help and there is no sign of any vaccum leaks
 
ya we have played with it and played with it the jets dont help and there is no sign of any vaccum leaks

Measure idle vacuum, then look and see what the power valve is, and SUSPECT the power valve is leaking even if the numbers are 'OK'

There's at least one tech article right on Holley's website on setting them up
 
What's the initial timing on your engine?

Fresh engine, no other carb tried?
 
You have to tell usssss just what that Holley is doing as for not running right.What is ya idle speed in P,lets start there.Holleys are so dam easy to tune easy I say.
 
First thing, check idle vacuum, the power valve should be 2" below idle vacuum. If your engine pulls 7", then you need a 4.5" power valve. This is typical with a big cam, then you want to get the main jets tuned in at about 3000 rpm cruise, then reset idle mixture and RPM, set WOT secondary jets, finally set the vacuum secondary opening rate with springs ( if vac secondaries)
 
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